Chart 1. Typical patterns of ammonia, nitrite and nitrate in a new aquarium.
This means that ammonia toxicity increases and deceases with pH. Aquariums with a higher pH will thus have more nitrogen in the toxic NH3 form and vice verse. When plants, algae and microorganisms remove ammonium from the water column, the equilibrium between NH3/NH4+ must be restored, thus NH3 molecules will protonate and form NH4+. This action will in turn reduce the amount in the NH3 form and act to reduce the toxic NH3 load.
The bacteria will colonise any and every surface in the aquarium, but have a preference for the filter media because the through flow of water provides a constant supply of both ammonia/nitrIte and oxygen. Ultimately the size of the bacteria colonies is restricted by the availability of these, but other constraints on stocking will restrict the number of fish that can be kept before this limit is reached.
Ammonia and Ammonium in the Aquarium - YouTube
Controlling Ammonia In A Fish Aquarium - Petcha
Like all living creatures, fish give off waste products (pee andpoo). These nitrogenous waste products break down into ammonia (NH3),which is highly toxic to most fishes. In nature, the volume of waterper fish is extremely high, and waste products become diluted to lowconcentrations. In aquariums, however, it can take as little as a fewhours for ammonia concentrations to reach toxic levels.Ammonia's toxicity to fish is very well know. Most aquarium and pond related books usually dedicate at least a paragraph or two on the subject. What is often not mention in many books is the relationship pH plays in the toxicity of the ammonia.The desired species of nitrifying bacteria are present everywhere(e.g., in the air). Therefore, once you have an ammonia source in yourtank, it's only a matter of time before the desired bacteria establisha colony in your filter bed. The most common way to do this is toplace one or two (emphasis on one or two) hardy andinexpensive fish in your aquarium. The fish waste contains theammonia on which the bacteria live. Don't overfeed them! More foodmeans more ammonia! Some suggested species include: common goldfish(for cold water tanks), zebra danios and barbs for warmer tanks, anddamselfishes in marine systems. Note: Do not use ``toughies'' or otherfeeder fishes. Although cheap, they are extremely unhealthy and usingthem may introduce unwanted diseases to your tank.Some call it the biological cycle, the nitrification process, new tank syndrome or even the start-up cycle. They all are referring to the same cycle - The Nitrogen Cycle. The aquarium nitrogen cycle is a very important process for the establishment of beneficial bacteria in the aquarium and in the filter media that will help in the conversion of ammonia to nitrite and then the conversion of nitrite to nitrates. Check out the aquarium water chemistry page (on the left) for more information on these terms.